(Reuters) - Italy's top winemakers are joining forces with the country's luxury goods elite as the world's second-biggest wine producer tries to give itself an edge in the battle for U.S. and emerging market customers amid falling consumption at home. Sales of Italian wine were flat at 12 billion euros ($16 billion) last year and recession at home, as the country drives through austerity measures to tackle a sovereign debt crisis, means the industry is becoming increasingly reliant on exports.